07-02-2018, 01:55 PM | #1 |
Drives: 2015 1LE Join Date: Oct 2015
Location: Cleveland, OH
Posts: 1,485
|
True 3" header connection
Just wondering if there is a big advantage of doing a true 3" connection up by the converters. Most 3" systems start out at 2.5" at the back of the converter and then go to 3". This is so stupid to me because that 2.5" restriction totally defeats the purpose of a 3" system. Was wondering if there is any good dyno data showing a true 3" system test with NO 2.5" restrictions.
|
07-02-2018, 04:44 PM | #2 |
Drives: 2010 SS/RS M6 BIG cam Join Date: Mar 2016
Location: McDonald's DT
Posts: 857
|
Or it creates a scavenging effect with increasing the volosity at that point
__________________
BIG cam ...... 305 45 18 Mickys ...... BMR suspensions
|
07-02-2018, 05:36 PM | #3 |
Drives: 2015 1LE Join Date: Oct 2015
Location: Cleveland, OH
Posts: 1,485
|
|
07-04-2018, 08:52 PM | #4 |
Slp kit is 3 in to header.
|
|
07-08-2018, 07:41 AM | #5 |
Drives: 2010 Camaro SS/RS Join Date: Mar 2014
Location: somewhere in MD
Posts: 4,883
|
I made some 3" collector extensions to remove the 2.5" section and the initial datalog after the new pipes were fitted showed a difference in fuel trims. My trims we're about 1-2% rich and went to 1-2% lean, some cells a little higher than 2%.
Now before anyone jumps to conclusions, I think it's from sealing exhaust leaks and not the 2.5" section. I had some decent ones in this spot and now the leaks are nearly non existent. I also sealed the connections after the x pipe as well. I'll log it again sometime next week to see if it goes back to running a little rich. I think it doesn't really matter too much unless you have a bigger cube motor, forced induction, or internal mods. It feels good knowing it's all 3" though lol
__________________
2010 2SS/RS
Z/28 intake, NW, FAST 102, speed engineering LT's, some exhaust, ATI -10% pulley, GM flex fuel injectors, DSX flex fuel sensor, MGW shifter, HP Tuners, some suspension work, stickers and a little weight loss. 12.63 @113.53 |
07-08-2018, 01:52 PM | #6 | |
Drives: 2015 1LE Join Date: Oct 2015
Location: Cleveland, OH
Posts: 1,485
|
Quote:
|
|
07-08-2018, 07:12 PM | #7 |
Drives: 2010 Camaro SS/RS Join Date: Mar 2014
Location: somewhere in MD
Posts: 4,883
|
It feels a bit different: the car seems to be able to get off the line better and it feels a little lighter overall. Not sure if it's from the exhaust now being all 3" or from sealing leaks. The pipes I removed were 3", then they went up to 4" to look like cats, and at the end they narrowed to 2.5" so they may have messed with the exhaust pulses/flow.
This was pretty inexpensive too. Maybe $40 bucks and a few hours
__________________
2010 2SS/RS
Z/28 intake, NW, FAST 102, speed engineering LT's, some exhaust, ATI -10% pulley, GM flex fuel injectors, DSX flex fuel sensor, MGW shifter, HP Tuners, some suspension work, stickers and a little weight loss. 12.63 @113.53 |
07-11-2018, 07:11 AM | #8 | |
Drives: 2011 Camaro SS 6sp Join Date: Nov 2016
Location: Drivers Seat
Posts: 1,904
|
Quote:
I bought TSP 2 inch headers with the dummy cats. Then I went to my exhaust guy and had him weld on 3 bolt flanges to my headers, and pipe it 3inch all the way to a pair of magnaflows. Never used the dummy cats. I guess it all depends on your plans with the car. If you just plan on bolt ons, you should be fine with the 2.5. He made it with 4 3 bolt connectors so the mid section can be easily removed. Glad he did, cause I just had to drop the tranny.
__________________
2011 Camaro SS---SOLD
TMS Dart 427 FED M311s, ESS Tuning G4 Blower, DSX Triple FP Assembly, DSX FF, FIC1300, Mcleod RXT 1200HD, Edlebrock Pro Flo XT 1158whp 1017wtq. 2010 CTS-V A6 - "Stock" SOLD 630whp 658wtq 2024 F-150 RCSB 5.0 4x4 waiting for tunes... |
|
07-11-2018, 06:06 PM | #9 |
Drives: 2015 1LE Join Date: Oct 2015
Location: Cleveland, OH
Posts: 1,485
|
Nice work, I am sure the restriction will cause a loss of power.
|
|
|
|
|